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Floating Pipeline 1

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jfreddy

Mechanical
Apr 21, 2016
13
GY
Hey guys i am in the process of doing a pre-feasibility study of using a floating pipeline to transport Heavy fuel oil to a bulk storage tank on shore. From google earth and onsite visits the floating pipeline would have to be laid on approximately 1.1 km (measurement at low tide) of mud flat since we are 2 meters below sea level.

My concerns are:

1) Can a floating pipeline be used under this condition given that it will be rested on slush during low tide.

2) Can HDPE be used? i have been researching using HDPE for transporting fuel oil but i have only seen applications with dredging and wastewater.

Any other information required please ask.
 
 http://files.engineering.com/getfile.aspx?folder=e11757be-2094-4e04-90b6-b65b48df084b&file=DSC00649.JPG
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Uuuugh - mud flats are terrible places to work or install anything.

In theory your floating hose might be OK, but the issues will be one of tides, currents, breaking waves, differential movements and the potential for parts of the line to become fixed in place whilst other bits float and move around. At 1.1 km it would move a fair amount unless it is restrained, but that then introduces stress, bending and requires strong anchors.

Burial, direction drill or putting it on supports with bridges between supports or solid pipe are much better options.

The environmentalists normally hate you for disturbing this and the potential for breakage and pollution is enormous, especially from a floating / flexible hose.

So to me it's a non started, even at feasibility level.

There is a reason why landfalls of pipelines are often concrete coated pipe buried with 2-3m cover and sometimes a rock armour layer on top. It might all be fine in the conditions in our photo, but when a storm comes in...... bye bye pipeline if left on the surface.

PE is a potential, but it can age in HC service, is susceptible to damage at high temps ( which is anything above 20C in PE design) and has a tendency to "sweat" with hydrocarbons and hence would leave a thin film of oil sheen on the water - generally not allowable.

HFO normally needs to be kept warm or hot during transport to stop waxing and reduce viscosity.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Pipelines floating around on mud flats is the worst thing you could think of doing. Short floating hoses on ship loading bouys are hard enough to keep running properly and there will be no dragging across the mud flats. Bury it well under the mud's scour depth, or put it on supports well above storm tide levels.
 
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